Is this possible (SLI)?

[alpha88]

I know it wouldn't be enabled by default or anything, but do you think it would be possible?

As far as I know, the 7800GTX and the 7900GT have the same number of pipelines and what not, just slightly different clock speeds.

 

[BassBomb]

thats an very interesting aspect, im gonna say it wont work because they are made on different processes, thus could be different under the skin

 

[alpha88]

I know they've been repipelined, but I *think* they are functionally equivalent. (just run cooler / or clock faster)

 

[HardWarrior]

That's a good question. They might know at SLIzone.

 

[Frostwake]

different cores, wont work obviously

 

[Bull Dog]

Originally posted by: alpha88
I know it wouldn't be enabled by default or anything, but do you think it would be possible?

As far as I know, the 7800GTX and the 7900GT have the same number of pipelines and what not, just slightly different clock speeds.

No.

.

 

[alpha88]

I don't see a logical reason why drivers could not be made such that they ran in alternate frame mode, since they can be clocked at the same speed, and perform the same.

 

[Pens1566]

I'm betting NO.

 

[Bobthelost]

Have you tried just connecting them and turning it on?

It'd be interesting to say the least to see if it worked.

 

[TheRyuu]

Originally posted by: Frostwake
different cores, wont work obviously

Duh!

The cores have to be the same in order for SLI to work. G70 and G71 are two different cores. Not only is the 90nm shrunken, but it seems to have some other things too like 50% shorter pipeline and other stuff.

So, NO it will not work.

 

[alpha88]

I'm not expecting that it would work out of the box, but I think that it can be done.

Having different cores shouldn't make a difference. Each core is assigned a task to work on independently (by the drivers). It would only make sense to do so if both can complete similar tasks at similar speeds, but identical cores should not be needed.

 

[Kakumba]

lets not forget, didnt the SLI bridge connector move slightly? if it did, you cant even connect it. and if you can connect it. no. its just not gonna happen.

 

[F1shF4t]

But it would be great if they got it to work, They could code the driver to share the load accross different cards but really it would be a huge pain in the *** to code but the outcome would make sli more viable for ordinary use. I mean if i could sli my 7800gt and 6600gt to just get a boost in newer games it would be sweet.

 

[moonboy403]

simply no

 

[seattledesi]

i agree.. i have a 6600gt and i want to sli it with a newer 7800.. it sucks that the cores have to be the same.. sounds like a marketing thing from nvidia.. they could have the drivers assign the tasks to the different gpus parallely.

 

[Nightmare225]

If you want to SLI, your best bet is to get one of the few remaining 7800GTXs left out there and SLI them.

 

[LittleNemoNES]

NO

 

[josh6079]

No, not yet, probably never. Not saying that Nvidia couldn't do it if they wanted to, but they won't want to because then you wouldn't have to buy another 7900. They wouldn't want that.

 

[Speedstream]

I had an original 7900gt KO from eVGA, i rma'd it with the issues that were surrounding the 7900 series. When I got the new 79KO I noted there were a few changes to the board itself. Needless to say, I could not get them to go into SLI mode. I'll be jumping on the big NO bandwagon for this thread before it fills up....so long as I can get a linux seat

 

[nitromullet]

Originally posted by: Speedstream
I had an original 7900gt KO from eVGA, i rma'd it with the issues that were surrounding the 7900 series. When I got the new 79KO I noted there were a few changes to the board itself. Needless to say, I could not get them to go into SLI mode. I'll be jumping on the big NO bandwagon for this thread before it fills up....so long as I can get a linux seat

That's interesting if I understand you correctly... You're saying that a new eVGA 7900GT KO with the Infineon RAM won't SLI with an eVGA 7900GT KO with Samsung RAM, correct? I'm surprised that eVGA could change that much on the card to break SLI compatability with a card of the same core, or maybe the old card just needs a BIOS flash.

 

[schneiderguy]

Originally posted by: Kakumba
lets not forget, didnt the SLI bridge connector move slightly? if it did, you cant even connect it. and if you can connect it. no. its just not gonna happen.

SLI works without the bridge connector

 

[nullpointerus]

I doubt it's possible with any currently released drivers. A unified video driver breaks the common 3D commands down into GPU-specific instructions that vary greatly, probably even amongst revisions of the same core. When nVidia implemented SLI, they probably just split the GPU-specific instructions amongst two different cards. So you'd have to disassemble the driver and completely rewrite that portion. And you'd have to support the least common denominator as far as features go, or at least shift the use of the newer features entirely to the newer core on a case-by-case basis. That's a lot of work and a lot of opportunities for new bugs.

 

[Speedstream]

the biosesez were not the same, I suppose I overlooked this. I don't know if you've seen the before & after pics of someone elses card, but here's the ones I have taken. I took pics of the changes I noticed right off.
http://frontiernet.net/~speedstream/vga_lawn/VGA/

 

[Acanthus]

Originally posted by: nitromullet

Originally posted by: Speedstream
I had an original 7900gt KO from eVGA, i rma'd it with the issues that were surrounding the 7900 series. When I got the new 79KO I noted there were a few changes to the board itself. Needless to say, I could not get them to go into SLI mode. I'll be jumping on the big NO bandwagon for this thread before it fills up....so long as I can get a linux seat

That's interesting if I understand you correctly... You're saying that a new eVGA 7900GT KO with the Infineon RAM won't SLI with an eVGA 7900GT KO with Samsung RAM, correct? I'm surprised that eVGA could change that much on the card to break SLI compatability with a card of the same core, or maybe the old card just needs a BIOS flash.

Bingo.

 

[Effect]

What i'd like to know is whether a volt-modded 7900gt 512mb could be fooled into running in SLI with a 7900gtx. Mind you, it would be cheaper to just buy 2 7900gt 512mb's, but it might help people who've already got a 7900gtx